Energy storage makes wind generation more reliable

Energy storage makes wind generation more reliable

For Ryan Jansen, one of the answers to energy sustainability is blowing in the wind."Wind is highly volatile," says Jansen, an associate research engineer in the area of Alternative Energy at the Saskatchewan Research Council (SRC). "On a macro scale (wind) evens out - today will be windy, tomorrow not so windy - but within that d ay yo u can have large gusts of wind."Jansen was part of a SRC wind-battery pilot project that looked at "smoothing" out that volatility by making a wind turbine act more like a conventional generator.

The project consists of an 800 kW Enercon wind turbine, along with a Saft battery capable of charging or discharging up to 400 kW for 90 minutes, located just north of Regina on the Cowessess First Nation.The pilot demonstration is meant to show what can be done with energy storage integrated with wind. "This is one of the first projects (of its kind) in the world," Jansen said.

By using wind power and battery storage together, the reliability of wind generation is improved and utilities can add more wind turbine to the grid, Jansen said."Our main goal was to prove the viability and reliability of the wind battery system. And show Saskatchewan, Canada and the world that this can work and this is the results we got."I think wind energy is a great opportunity," Jansen said. "I think we have good resources in Saskatchewan and if there is an existing power purchase agreement, then it's a good alternative."

The project had a power purchase agreement with SaskPower and the energy generated was added to the power grid.SRC is now looking for further opportunities to showcase energy storage, specifically with wind turbines.

"This is all scalable," Jansen said. "You could look at large wind farms with large battery system or depending on the application, you might do just one turbine with one battery."

How it works

The battery monitors the instantaneous output of the wind turbine, and automatically charges or discharges in an effort to smooth or steady the output of the wind turbine, thereby improving the turbine's predictability. "You can get big spikes on the wind turbine that we have," Jansen said. "The idea with energy storage is you can smooth out those spikes and make it more predictable."

Findings

By using energy storage, the project found they were able to smooth these spikes by up to 78 per cent, meaning more wind turbines could be put on to the grid without negatively affecting power quality or reliability.

Firming

They were able to prove the system could maintain a minimum threshold of power from the site. "We could set the turbine battery system to output a minimum threshold of about 275 kW, which is the average power of the turbine over a year," he said.This turbine could power the equivalent energy of about 300 homes a year. A utility could always depend on this minimum threshold.

Dispatchable Wind

They were able to take energy from off-peak hours, store the energy in the batteries for use during peak hours. Jansen said that is important because there is no guarantee of sufficient wind power during peak hours in the morning when everyone is getting up and then again in the late afternoon when everyone gets home from work. "Energy storage, such as the system we're demonstrating, can provide immediate response to these energy needs, improving the reliability of wind turbine generation."